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Theories with low-energy supersymmetry predict the existence of stable nontopological solitons, Q-balls, that can contribute to dark matter. We discuss the experimental signatures, methods of detection, and the present limits on such dark-matter candidates. [S0031-9007(98)

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Applying our recently developed propagation code we review extragalactic neutrino fluxes above 10 14 eV in various scenarios and how they are constrained by current data. We specifically identify scenarios in which the cosmogenic neutrino flux above ≃ 10 18 eV, produced by pion production of ultra high energy cosmic rays outside their sources, is considerably higher than the "WaxmanBahcall bound". This is easy to achieve for sources with hard injection spectra and luminosities that were higher in the past. Such fluxes would significantly increase the chances to detect ultra-high energy neutrinos with experiments currently under construction or in the proposal stage.

We have searched for intermediate-scale anisotropy in the arrival directions of ultrahigh-energy cosmic rays with energies above 57 EeV in the northern sky using data collected over a 5 yr period by the surface detector of the Telescope Array experiment. We report on a cluster of events that we call the hotspot, found by oversampling using 20 • radius circles. The hotspot has a Li-Ma statistical significance of 5.1σ , and is centered at R.A. = 146. • 7, decl. = 43. • 2. The position of the hotspot is about 19 • off of the supergalactic plane. The probability of a cluster of events of 5.1σ significance, appearing by chance in an isotropic cosmic-ray sky, is estimated to be 3.7 × 10 −4 (3.4σ).